Baby fish breathe easier around large predators

Fig 1

Small – hungry mesopredator common on coral reefs. Photo: C.E. Mirbach

This blog post is a press release from the authors of Journal of Animal Ecology paper “Top predators negate the effect of mesopredators on prey physiology” by Maria M. Palacios et al. Press release issued by by James Cook University & ARC Centre of Excellence for Coral reef Studies

Scientists have discovered that the presence of large fish predators can reduce stress on baby fish.

The researchers – from the ARC Centre of Excellence for Coral Reef Studies, James Cook University and the University of Glasgow- have found that physiological stress on baby fish can be reduced by more than a third if large predatory fish are around to scare off smaller, hungry predators, known as mesopredators. Continue reading

How climate change could exacerbate the impacts of large mammal declines

Deer in small wooded patches

Deer in small wooded patches on the campus of Princeton University. The photos were taken as part of an undergraduate ecology laboratory course taught by my co-author Rob Pringle, and for which I served as an assistant instructor. Students also captured images of foxes, raccoons, and house cats.

In wintertime, it’s often getting dark in Princeton by the time I head home from the office to scrounge up some dinner. Along the half-mile path, I regularly walk or bike within few meters of the local herd of white-tailed deer. There are at least five or six animals that circulate among the tiny patches of trees and streams at the south end of campus. The university deer are just a fraction of the estimated 450-500 that roam the 16 km2 town of Princeton. That’s almost 40 deer per km2, well above the state of New Jersey’s recommended 20-25 per km2. Indeed, much of the northeast U.S. is forced to deal with dense, growing deer populations thanks to the removal of wolves, forest recovery over the last century following the westward shift of American agriculture, and a suburbanization-associated decline in hunting.

All these extra ungulates come with costs. For one, Princeton has paid hundreds-of-thousands of dollars between 2001 and 2015 to professional sharpshooters who controversially culled over 2700 deer from the population. However, hunting costs pale in comparison to those of the 300-plus deer-vehicle collisions that occurred each year in Princeton before the hunts were organized! Continue reading

New Associate Editors

Journal of Animal Ecology is pleased to welcome Sandra Bouwhuis (Institute of Avian Research, Germany), Anna Eklöf (Linköping University, Sweden) and Elisa Thebault (Université Pierre et Marie Curie, France) to the board of Associate Editors. They have all joined on a three-year term and you can find out more about them below. Continue reading

Researchers discover complex effects of temperature shifts on both hosts and parasites

JAE-2015-00750.R1This blog post is a press release from the authors of Journal of Animal Ecology paper “Host and parasite thermal acclimation responses depend on the stage of infection” by Karie A. Altman et al. Press release issued by Oakland University

 

While climate change is often associated with global warming trends, it is also believed to influence patterns of temperature variability, with greater and more frequent shifts in temperature from one day to the next. Those temperature shifts could change the way certain species interact with each other. Continue reading

Lethal genetic blindness found in a rare Scottish bird

JAE-2015-00734.R1This blog post is a press release from the authors of Journal of Animal Ecology paper “Evidence of the phenotypic expression of a lethal recessive allele under inbreeding in a wild population of conservation concern” by Amanda E. Trask et al. Press release issued by University of Aberdeen

The last remaining Scottish populations of the rare red-billed chough are being affected by a genetic mutation causing lethal blindness, a new study from the University of Aberdeen and the Scottish Chough Study Group and funded by NERC and Scottish Natural Heritage has shown.

Blindness was first observed in a chough chick in 1998 and small numbers of blind chicks have occurred in most years subsequently. Continue reading

Solving the skewed sex ratio on science journal editorial boards

On this blog in October 2014, Senior Editor, Tim Coulson presented an argument for solving the sex ratio problem in scientific academia. He proposed that we should mandate that universities and institutes appoint equal numbers of men and women at each professional level from faculty positions though to full professors. Whilst the skewed sex ratio in academia has been long recognised and discussed, there is another bias much closer to home that has received significantly less attention: the male-bias on many science journal editorial boards. To coincide with International Women’s Day on March 8th, I thought it would be useful to highlight this important issue.

Back in 2014, just 13% of Journal of Animal Ecology Associate Editors were female, and none of our Senior Editors were. Whilst sex ratios on other ecology journals were generally much better than this, none of them were anywhere near to sex ratio parity. So, why was this and what have we done to try to remedy this?

Journal of Animal Ecology has four senior editors, three of whom (Ben Sheldon, Jean-Michel Gaillard and Nate Sanders) have been appointed in the last 2-3 years. During this period, we strongly encouraged women to apply, but we received only a small handful of applications from women. Did we do enough to encourage experienced women to apply? Evidently not. Each of the Senior Editors involved in the shortlisting processes did informally encourage good candidates to apply – both female and male – and all of our Associate Editors at the time were also encouraged to apply. In addition, the advertisements for the positions, specifically suggested that we wanted applicants who would add to the ‘diversity’ of the Senior Editor board.

So what can we do to address this issue? We could pledge to always interview at least one female applicant, regardless of where they rank overall on our shortlist (a sort of female Rooney Rule). But based on previous pools of applicants, I am sceptical as to whether this would be of help in the ultimate goal of recruiting female Senior Editors. A different approach is required. Perhaps the solution to our Senior Editor problem is to appoint more female Associate Editors, in the hope that it will promote a stronger pipeline to the senior positions.

Correcting the male-bias of the AE board is a laudable goal in itself, of course, and for the last 2-3 years we have been taking positive action to appoint more female AEs. This is not to say that we have exclusively appointed only women, but we have followed a policy of first exhaustively considering a pool of potential female candidates. In so doing, we have improved the sex ratio from 13% in 2014 to 36% in March 2016. This has been a relatively easy process, but has not been without issues. From personal experience, I have found that when we approach suitable male candidates for AE positions, the first response is generally very positive and mostly they accept without further discussion. In contrast, female candidates are much more likely to either decline immediately due to other commitments (this is especially true of non-tenured professors in the US), or to request further information about the role and the time commitment involved. Of course the latter is a very sensible approach and perhaps just reflects a difference between the sexes in common sense!

It is my hope to achieve equality on the AE board in the not too distant future. Once we achieve this target, we hope that it can be maintained in the long term, but this will probably not happen without continued positive action, as the pool of suitable individuals (mostly experienced early-mid career faculty) is consistently male-biased.

To stimulate further discussion on these issues, I asked one of our Associate Editors, Sheena Cotter, to think about them from her personal perspective as an early-mid career female academic. Her response is below and will, I hope, encourage others to enter the discussion.

One final thought. Gender, of course, is not the only diversity issue academic journals face. I write this blog from the Universidade Federal de Viçosa in Brazil, where I have just given a presentation to staff and students on ‘How to Get Published’ from an Editor’s perspective. For my audience, an equally pressing issue is how we address the geographical and ethnic imbalance of the editorial board (and, indeed, of the papers we publish), which is still overwhelmingly in favour of white Europeans and North Americans. If we can simultaneously address all of these issues, we will be doing very well indeed.

Let us have your thoughts.

Ken Wilson, Senior Editor
@spodoptera007

A response from one of our female Associate EditorsCotter, S

When Ken told me that the editorial board of JAE had been just 13% female when he took over as Senior Editor, I wasn’t particularly surprised. The pool is smaller. The number of women in ecology is very close to parity at undergraduate, PhD and postdoctoral levels, but then starts to decline dramatically. To be approached to be an Associate Editor, a woman would have to have a certain level of experience, and by lecturer level there are already fewer females than males. I also suspect women may be less prominent than men at the same stage of their career. If the choice of who to approach is determined in part by who you are aware of in a certain field, then this may be driven by how much scientists promote themselves via networking at conferences, organising meetings and seminars, sitting on grant committees etc. It is likely that women with young families spend less time on these activities than men as they typically require time spent away from home.

There is also “unconscious bias” associated with gender. We are all susceptible to it, I don’t recall a single female lecturer when I was an undergraduate and I doubt I remarked upon it, because scientists were always men. I’m still sometimes surprised when an ambiguously named scientist turns out to be female, my default assumption is male. This may seem fairly harmless until you are in a position to recruit and you may inadvertently prefer a male candidate over an equally, or better, qualified female one. So to increase the percentage of female AEs you just have to identify suitable candidates and approach them, right? Well, apparently not, because it seems that women are more likely to say no. This was a surprise.

When I was approached to take on the role of Associate Editor for JAE, I was delighted and jumped at the chance. However, at that point I was a NERC fellow with minimal teaching duties and no children. The potential extra workload didn’t cross my mind. But many potential female candidates for AE will be trying to balance a heavy workload and a young family and may be loath to add to that burden. Before I had kids I couldn’t understand the claim that having children was the reason that women dropped out of academia, because most women don’t have children on their own, they have them with men, and presumably there are as many men with young families as there are women. So what’s going on? Of course, I don’t really know the answer, I can only talk from personal experience.

First, the physical act of carrying and then delivering a child (or two – I’m lucky enough to have twins…) is physically exhausting. I couldn’t work as hard while I was pregnant as I could beforehand. Second, it takes over your brain in a way that it doesn’t seem to for the father. Babies become real to women much earlier on in the process than they do for men. I spent so much of my time thinking and reading about pregnancy, the birth, new babies, what we’d need to buy, how our lives would change etc., that I really got hardly any work done at all. Once the baby is born, something happens to your brain, at least in the short term, and this is something that highly intelligent female colleagues have also experienced. I found it incredibly difficult to concentrate on science when my children were babies. I don’t think this really happens to men. They might still be very involved and do their fair share around the house and take their turn at night feeds (if possible) but I don’t think they experience the “brain melt”, and this takes a while to get over.

Now that my children are a bit older (2, 2 and 4), I think my brain functions just fine, but my priorities have definitely changed. I used to quite regularly stay late at work during the week and at the weekends, but now I always leave work by 5pm and only work in the evening on weekends if I absolutely have to. I am not prepared to miss the evening with my children during the week. At the weekend, I spend the day with my children and running around after 3 small ones from 6am to 7pm is pretty exhausting so working in the evening is a challenge. Shouldn’t this be true of men too? I’m sure it is true of many men, but I have also worked with several male colleagues at the same career stage as me, with young children, who regularly stay late at work. I’m not aware of any women who do this. So if I was asked to be an AE now would I jump at the chance? Of course I would, but I know what to expect; if I didn’t, given my massively increased workload since becoming a tenured lecturer and the increased priority of time with my children, if I didn’t know what to expect I’d certainly ask!

So how do we increase the number of female AEs? We approach suitably qualified female candidates and make it clear that the workload isn’t onerous and you can balance it by reducing the numbers of papers you accept to review. It is a prestigious position, increases your profile and looks good on your CV. It is vital to increase the visibility of female scientists as this can help to redress the unconscious association of “science” with “men” and increasing the pool of experienced female AEs will hopefully result in one of us applying to be a Senior Editor in the near future – watch out Ken!

Sheena Cotter, Associate Editor

Demography beyond the population: Integrated demography comes of age

Assessing variation in population abundance over time and across space is a long-standing goal of population ecologists. Up to now, two main approaches have been mostly used to identify the factors driving observed fluctuations in population abundance. First, a pattern-oriented approach, based on the monitoring of population size, involves the analysis of time series of counts. In the most recent applications, these analyses lead to partitioning observed changes in population growth into different contributing factors, like current or past population density, environmental conditions, or demographic stochasticity. Second, a process-oriented approach, based on the monitoring of demographic parameters, involves the construction of age- or stage-structured demographic models. The steady increase of case studies aiming to monitor known-aged recognizable animals over most of their lifespan, the availability of statistical methods allowing reliable estimates of demographic parameters to be obtained from field data, and the development of a powerful framework to build a large range of matrix population models have all led to this process-oriented approach becoming a standard tool of population ecologists. It has become the gold standard in the context of both the management of exploited populations and the conservation of endangered populations. However, analyses of detailed monitoring of individuals have also revealed the existence of marked individual differences in most life history traits studied so far, which have been mostly ignored until now when using population-scale demographic modelling. To account for such sources of within-population variation, a trait-based demographic approach is required. Nowadays, Integral Projection Models (IPMs) provide a way to obtain more realistic demographic models that encompass the association between demographic parameters and, for instance, phenotypic traits. In their most extended version, IPMs include the four biological functions that are necessary and sufficient to obtain the distribution of a given continuous trait in a population at a given time from the distribution of the same trait in the same population one time-step before. These functions are the survival function linking survival probability to the trait value, the recruitment function linking the number of recruits to the trait value, the growth function linking the trait value at time t+1 to the trait value at time t, and the inheritance function linking the trait value of the offspring to the trait value of the parents.

Following the British Ecological Society Symposium “Demography Beyond the Population” that was held in Sheffield about one year ago, four papers derived from this symposium have just been published in Journal of Animal Ecology as part of the British Ecological Society Cross Journal Special Feature: Demography Beyond the Population. From the analysis of the contents of these four papers it appears that a new, integrated demography, comes of age. Continue reading

Demography Beyond the Population

jane_v85_i2_cover

Experimental population of soil mites Sancassania berlesei. Past environments shape the distribution of phenotypic traits via selection and plasticity. One such trait, individual body
size is commonly used in size-dependent demographic analyses to represent the effect of the environment on vital rates. However, experimental populations of soil mites maintained in different food environments revealed that the strength of body size as a proxy for past and current environmental effects can vary vastly among vital rates (see Brooks et al.). Photo by Marianne Mugabo.

This exciting collaborative and interdisciplinary special feature integrates novel lines of research in the vast field of demography that directly interact with other ecological and evolutionary disciplines.

The goal of the special feature is to highlight the interdisciplinary potential of demography and is further emphasised by the fact that the 21 articles are spread across all six journals of the British Ecological Society.

The goal of the Special Feature is to highlight to both demographers and non-demographers alike that there is much to be gained by linking demography to other disciplines and scales in ecology and evolution.

The Special Feature is based on a British Ecological Society symposium that was held in March 2015 and is the first time all six BES journals have collaborated to produce a joint special feature.

Journal of Animal Ecology has published 4 papers in the Special Feature:

Disentangling correlated explanatory variables

In this paper Brooks et al. discus how the the strength of size as a proxy for past environments varies among vital rates. They quantified this using a novel method for understanding nonlinear relationships between responses and multicollinear predictors. This non-mechanistic model has the strength of being flexible enough to apply in data-limited situations and will be useful for identifying patterns and generating hypotheses.

The evolution of labile traits in sex- and age-structured populations

Childs et al. present a data-driven framework that  has the potential to facilitate greater insight into the nature of selection and its consequences in settings where focal traits vary over the lifetime through ontogeny, behavioural adaptation and phenotypic plasticity, as well as providing a potential bridge between theoretical and empirical studies of labile trait variation.

Opportunities and challenges of Integral Projection Models for modelling host–parasite dynamics

Epidemiological dynamics are shaped by and may in turn shape host demography. Here, Metcalf et al. extend statistically derived population models that explicitly account for variance in individual trajectories commonly used for plant and animal demography (Integral Projection Models) to capture the process of infection and propagate it across scales.

Des différences, pourquoi? Transmission, maintenance and effects of phenotypic variance

In this paper Plard et al. discuss how the influence of phenotypic variation on population dynamics is much higher in short-lived than in long-lived life-histories.

Also in the issue COMADRE: a global data base of animal demography has been published,  the paper that introduces the COMADRE Animal Matrix Database,  find out more in this blog post.

Simon Hoggart
Assistant Editor, Journal of Animal Ecology
@AnimalEcology

Global demography in the animal kingdom

Today the paper that introduces the COMADRE Animal Matrix Database was published in Journal of Animal Ecology (Salguero-Gómez et al. 2016). This is an international effort in collaboration with ca. 10 other institutions. Our main goal was to replicate the impact that its sister database, the COMPADRE Plant Matrix Database (Salguero-Gómez et al. 2015) has had for plant ecology and evolution, but in the rich animal kingdom. Open access to the database itself can be gained from the COMADRE website.

comadre logo Continue reading

A Look Back At 2015 … And A Little Peek Forward

It’s been another busy year at Journal of Animal Ecology, with more personnel changes and a few new initiatives. Here, we review some of these developments.

Papers and other media

Last year was another good year for the journal, with our Impact Factor remaining strong (4.504), ranking us 2nd out of 149 Zoology journals and 24th out of 143 Ecology journals. We continued to publish a number of successful Feature papers, including two How to.. papers, which continue to be extremely popular with our readers. The first, by Marie-Therese Puth, Markus Neuhäuser and Graeme D. Ruxton ‘On the variety of methods for calculating confidence intervals by bootstrapping’ and the second, by Damien Farine and Hal Whitehead, on ‘Constructing, conducting and interpreting animal social network analysis’. The latter was accompanied by a Virtual Issue on social network analysis, edited by Senior Editor Ben Sheldon. We also published a joint Virtual Issue with Journal of Applied Ecology and Methods in Ecology and Evolution on ‘Monitoring Wildlife’, featuring a selection of papers focusing on new methods and technologies for monitoring animals in their natural environments. To coincide with Open Access Week in October 2015, the five BES journals published a Virtual Issue of a selection of our OA papers. We also welcome unsolicited inquiries about potential Virtual Issues, whether you would like to see a particular topic covered, or whether you would like to edit one yourself. Similarly, we continue to welcome other special features including Synthesis, Review and How to.. papers, as well as topical Forum articles, so if you have any ideas, please let us know. Continue reading

Do animals exercise to keep fit?

This blog post is a press release of the Journal of Animal Ecology paper “Do animals exercise to keep fit?” by Lewis Halsey. Press release issued by The British Ecological Society

From joining a gym to taking up running, getting fit is a perennially popular new year’s resolution. We lead sedentary lifestyles and have easy access to energy-rich food, so we need to do voluntary exercise in order to keep fit. But what about other animals? Does a harbour porpoise, perhaps, need to put in extra training to ensure it can out-swim the dolphins that hunt it? Do animals exercise to keep fit?

It’s a question Dr Lewis Halsey of the University of Roehampton ponders in a new paper published today in the Journal. And the surprising answer is that we don’t know – because it is an issue that has gone almost entirely unstudied.

Animals need energy for growth and for locomotion, for attack and defence, and ultimately for reproduction. Yet animals can only obtain energy intermittently by foraging, storing some of it to use later, so the energetic ecology of an animal is fundamental to its success.

As an eco-physiologist, Halsey studies how animals expend energy, and how they adapt their behaviour and physiology to reduce their energy costs. On Sundays he goes running on Wimbledon Common.

“It made me think about my own biology and ecology. If I don’t exercise I get less fit, and am less able to do highly active things. So I wondered if some animals need to spend time and energy on voluntary exercise so that they are fit enough to out-run predators, win over mates or hunt down prey,” he explains.

But when he searched the literature, he found very few studies on the matter. “Researchers haven’t contemplated the idea that some animals may not do enough exercise during their general activities to be suitably fit for infrequent, high-intensity activities such as fleeing from predators. This needs to change,” says Halsey.

His new paper, which he hopes will encourage more research, outlines a set of concepts and the experiments that could be used to test them. But despite the lack of direct evidence, he points to some intriguing animal studies – from polar bears and penguins to giant pandas and barnacle geese – that suggest the answers might depend on an animal’s ecology.

According to Halsey: “We know that animals change their body condition in response to environmental conditions. Songbirds may put on some weight to survive the winter, but not too much if predators are around lest they become slow at escaping. And harbour porpoises, if regularly preyed on by dolphins, become much sleeker and carry less body fat so that they can out-swim their attackers.”

There are examples, too, of animals getting fatter when they have no predators to fear. This could explain why laboratory animals pile on the pounds (even though mice and rats will voluntarily run on wheels provided), and why giant pandas are so sedentary. During the day, giant pandas walk on average just 27m in an hour, but their presumed low aerobic fitness may not concern them because they no longer have predators to worry about.

Other species can maintain key aspects of their fitness without doing any voluntary exercise. In the polar regions, polar bears and penguins burn different tissues while fasting. During hibernation polar bears maintain crucial muscles so that they are still physically strong when they wake up. And while king penguins lose lots of muscle during their fasts on land, they seem to be able to get fit very quickly once they return to sea to fish.

Barnacle geese appear to be an extra special case of getting fit quickly. Some populations migrate 2,500km each autumn from Svalbard to Scotland, yet in the run up to migration they fly for only a few minutes each day – short bursts of flight that perhaps mirror the modern high-intensity training (HIT) regimes human athletes use to boost maximal aerobic capacity.

But according to Halsey: “Barnacle geese appear to get fit for certain predictable, planned events such as migration and yet miraculously seem able to do so with little or no voluntary exercise. So their bodies seem to trigger increased fitness from within – they get fit automatically when they need to – enough to make any human with a waning new year’s resolution to get fit very jealous.”

Finding out more about whether animals exercise to keep fit could have important scientific implications, challenging existing orthodoxy on animal ecology and behaviour, says Halsey.

“If animals are undertaking activities solely or partly to keep fit, this opens up a significant new facet to our understanding and interpretation of animal behaviour. No-one has previously observed animal behaviours and thought ‘this behaviour could be associated with keeping fit’,” he explains.

“On top of this, if indeed some animals have to ‘keep fit’ then the activity involved could burn important energy reserves, which feeds into fundamental ideas of optimality, where animals are expected to expend time and energy in ways that maximise their short- or long-term success.”

For more information contact Dr Lewis Halsey, University of Roehampton, email: l.halsey@roehampton.ac.uk, mob: +44 (0)7779 784523

Dr Lewis Halsey (2016). ‘Do animals exercise to keep fit?’, doi: 10.1111/1365-2656.12488

How a Special Feature can help wildlife “Stuck in Motion” – Video post

In an epoch that will likely be remembered as “The Anthropocene”, wildlife is struggling to cope with anthropogenic habitat loss, fragmentation and disturbance. Ancient migration routes are being lost as we speak, and animal space use, behaviour and life history are undergoing rapid changes. “Villy” and his Norwegian wild reindeer pals are extremely wary of human activities, and may be considered emblematic of the challenge of human-wildlife coexistence.

We believe that science can help. The first step is to single out key ecological questions, and to identify the most appropriate technologies and methodologies to answer them. Proper analyses of GPS-tracking data have recently provided scientists with unprecedented opportunities to understand mechanisms underlying the observed patterns and processes of animal space use, and to make inferences and predictions needed to guide sustainable development and support human-wildlife coexistence. Continue reading

The secret life of wild reindeer

This post presents photos from the Special Feature” Stuck in motion? Reconnecting questions and tools in movement ecology ” from the current issue (85:1) of Journal of Animal Ecology

DCIM101MEDIA

Wild mountain reindeer. Photo: wild reindeer.

Taken from GPS collars equipped with wide-angle cameras, these amazing shots represent an unprecedented window into the lives of reindeer, one of the most ancient deer species in the world. Few people are aware that within the heart of Europe there still exist mass migrations as spectacular but more secretive than those in the Serengeti. Yet, reindeer migrations represent one of the most endangered phenomena in the Northern hemisphere. Wild reindeer are extremely wary of humans, who have been harvesting them since pre-historic times using large-scale pitfall systems. Their anti-predator strategy consists of aggregating in large herds roaming across vast mountain plateau in southern Norway, and avoiding human activities. Following the industrial revolution, the development of anthropogenic infrastructures has therefore led to the fragmentation of the last remaining wild mountain reindeer population into 23 virtually isolated sub-populations, and has hampered/blocked migration routes used since pre-historic times. Due to the increase in tourism, hydropower and other human activities in mountain areas, fragmentation is rapidly ongoing. Continue reading

When does ecology of fishes became fisheries research?

Photo11_11_crop

World fisheries day, celebrated today aims to draw attention to the poor status of many fished species as a consequence of overfishing, habitat degradation, global warming, and pollution. Clearly, we stand far from the key objective of fisheries management, that is, to regulate fishing such that in the long term harvesting is sustainable. Less political and more science-based management has frequently been called upon as a solution and ‘ecosystem-based fisheries management’ is a term often repeated, but rarely implemented. In fact, a recent study by Skern-Mauritzen et al. (2015) showed that out of 1200 reviewed fisheries, ecosystem-based drivers were only accounted for in 24 cases. Continue reading

Bugs collected on rooftop for 18 years reveal climate change effects

This blog post is a press release from the authors of the Journal of Animal Ecology paper “Resource specialists lead local insect community turnover associated with temperature – analysis of an 18-year full-seasonal record of moths and beetles” by Thomsen et al. Press release issued by University of Copenhagen

Horse-chestnut leaf miner (Cameraria ohridella) and acorn weevil (Curculio glandium) Photo credit: Jens Kirkeby (above) and Klaus Bek Nielsen.

Horse-chestnut leaf miner (Cameraria ohridella) and acorn weevil (Curculio glandium) Photo credit: Jens Kirkeby (top) and Klaus Bek Nielsen (bottom).

A volunteer registration of insects for 18 consecutive years on the Copenhagen roof of the Natural History Museum of Denmark has revealed local insect community turnover due to climate change. The research suggests a pattern of specialised species being more sensitive to climate change.1543 different species of moths and beetles and more than 250,000 individuals have been registered on a single urban rooftop in Copenhagen over 18 years of monitoring. That corresponds to 42 % of all the species of moths in Denmark and 12 % of the beetles. More interestingly, the insect community has changed significantly during that period. The results are published in the Journal of Animal Ecology led by researchers from the Center for Geogenetics and the Center for Macroecology, Evolution and Climate at the Natural History Museum of Denmark at the University of Copenhagen.

“As temperature increases we see a corresponding change in the insect community, specifically for the resource specialists – the insects that feed on only one species of plant. Earlier studies have confirmed that specialist species also respond rapidly to destruction of their habitats, so we are dealing with a very sensitive group of animals” says one of the lead authors postdoc Philip Francis Thomsen from the Center for Geogenetics. Continue reading

Spatial overlap in a solitary predator

F97, a subadult female raised by F61. Photograph by Patrick Lendrum / Panthera.

F97, a subadult female raised by F61. Photograph by Patrick Lendrum / Panthera.

F61 and F51, adult female cougars (Puma concolor), also called mountain lions, were very nearly the same age when they gave birth to their first litters of kittens within a month of each other in 2011. The pair of big cats were neighbors in adjacent and overlapping home ranges in the Bridger-Teton National Forest, east of Grand Teton National Park in northwest Wyoming, USA.

A well-placed motion-triggered camera caught a fortuitous image of F61 and F51 spending time together in early 2012, accompanied by their four kittens (1 from F61, 3 from F51). It sparked great discussion among our team, many of whom were convinced they must be close relatives, perhaps sisters. Indeed, prevailing theory supported the idea that close kin were more likely to be close to each other and tolerant of one other. Thus, it just made sense that the two cats would be kin. At the time, however, we did not know the genetic relatedness of cougars in our study, except of course, kittens born to females we were tracking. Continue reading

Accurate timing of migration prolongs life expectancy in pike

This blog post is a press release from the authors of the Journal of Animal Ecology paper “Causes and consequences of repeatability, flexibility and individual fine-tuning of migratory timing in pike” by Petter Tibblin published today. Press release issued by Linnaeus University

Animal migration is a spectacular phenomenon that has fascinated humans for a long time. It is widely assumed that appropriate timing of migratory events is crucial for survival, but the causes and consequences of individual variation in timing are poorly understood. New research based on migrating pike in the Baltic Sea and published in the British Ecological Society’s Journal of Animal Ecology reveals how behaviours such as punctuality, flexibility and fine-tuning influence life expectancy in fish. Continue reading

From social network analysis to speciation in the Neotropics: exciting research by early career ornithologists.

Mentoring in action: the networking event that occurred after the lightning talks by early career ornithologists that I described in my earlier post.

Mentoring in action: the networking event that occurred after the lightning talks by early career ornithologists that I described in my earlier post.

As I mentioned in my earlier post, the joint American Ornithologists Union (AOU) and Cooper Ornithological Society (COS) conference this year emphasized a renewed focus on early career professionals.  Such a practice is key in supporting early careers folks in a time when the job market is tight and funding rates are very low.  Many of us may receive quality one-on-one mentoring at our home institutions, but this type of feedback in a conference setting from individuals that may be on search committees or grant review panels is also invaluable. AOU is not the only organization to recognize this need. The Society for the Study of Evolution (SSE) also provides opportunities for one-on-one mentoring for early career professionals, and I’m sure readers can name other scientific organizations and conferences that do the same.  In all, this is an important movement among organizations to foster the next generation in tangible ways.  Keeping in the spirit of this movement, I’d like to highlight papers given by early career individuals from the AOU-COS 2015 conference.

Jared Wolfe, trained in Phil Stouffer’s lab at Louisiana State University and now with the USDA forest service, gave one of the Cooper Young Professional presentations.  Using one of the more elegant sets of slides I’ve seen, he presented research by himself and colleagues in the Stouffer lab on the impact of second growth forest on the behavior, survival and biogeography of birds in the Amazon.  This research was based in the Biological Dynamics of Forest Fragments Project (BDFFP), started in 1979 by Thomas Lovejoy near Manaus, Brazil. The BDFFP consists of a series of differently sized old growth fragments that are being reconnected by second growth forest of different ages. Comparing this incredible study site to a series of islands created by flooding in a nearby area around the same time, Wolfe and colleagues were able to demonstrate that, at least for birds, forest fragments do not behave like islands in terms of species composition or survival. They also asked whether second growth is ‘bad’ or ‘good’ habitat.  By comparing fragments embedded within variably aged second growth (from <5 years to >10 years), they demonstrated that edge birds do well with young second growth whereas insectivorous understory birds do not. As the second growth matures, they found that young insectivorous understory birds begin to recolonize regenerating forest and it was hypothesized during Q&A that the most sensitive bird species may recover after 60 years of regeneration. Perhaps the most interesting finding to me was that networks of mixed- species flocks were quite unstable in second growth itself, but began to exhibit a more complete network in fragments connected by second growth.  It is worth noting that these results are the work of thousands of hours of netting, surveying and following birds with radio telemetry in difficult field conditions year round.  Of great interest to Neotropical ornithologists who do not have a trusty Pyle guide to turn to, Wolfe and Erik Johnson have worked out aging techniques based on molt cycles and plumage patterns for a number of tropical species, which will open up new avenues of research on these birds.  Very exciting! Expect that work out soon through the Studies of Avian Biology.  Finally, I should note that Wolfe and two colleagues, Luke Powell and Jacob Cooper are working to address the same questions in Equatorial Guinea, Central Africa, as well as conserve rapidly disappearing species in that region.  Be sure to check out their endeavors (https://www.facebook.com/egbirds) and future publications!

Maya Faccio, a Ph.D. student in the Weir Lab at the University of Toronto, gave a great talk on the genomics of speciation in the Hypocnemoides Amazonian complex. The ranges of many Amazonian birds are defined by river barriers and generally are thought to drive speciation in allopatry.  Faccio and colleagues examined the black chinned antbird (H. melanopogon) and band-tailed antbird (H. maculicauda) that come into geographic contact along the eastern edge of their range.  They used a genome-wide SNP dataset and fastsimcoal2 to test whether these sibling species evolved via speciation in allopatry with secondary contact or whether parapatric speciation is in play.  A model of parapatric speciation was rejected, and the best model was one of an initial allopatric phase followed by secondary parapatry. I was taken by this talk because the genomics of speciation is still a relatively recent field, and focused primarily on model taxa or non-model taxa in temperate regions. I was impressed to see a well-executed genomics approach to a speciation question in a tropical bird species by a graduate student.  Keep an eye out for this student’s work!

Elizabeth Hobson, trained in Tim Wright’s lab at NMSU and now a postdoc at the National Institute for Mathematical and Biological Synthesis, was one of the early career professionals who took part in the lightning slide talks this year at AOU. Dr. Hobson integrates behavioral assays and cutting edge network analysis to address questions about the emergence of group-level social structures. Using novel captive groups of monk parakeets (Myiopsitta monachus), she asked questions about whether rank affects how individuals decide to target aggression and potential cognitive mechanisms involved in inferring own and others’ ranks.  Rank does affect target choice, and after a week of settling into new groups, individuals shift in behavior to preferentially target aggression against those nearby in rank. Her modeling work revealed that individuals could use subsets of the aggression network to infer third-party relationships.  This ability for social memory and inference allows individuals to avoid costly social interactions and instead target those most likely to threaten their own position in rank. Plus, the network models make for great visualizations of quantitative (behavioral) information!

There were many more excellent talks and posters given by early career ornithologists, and I congratulate the organizers, Eli Bridge and Jeff Kelly, for putting together an engaging, intimate AOU-COS meeting this year.  Be on the look out for next year’s exciting, largest-ever North American Ornithological Conference, NAOC 2016.

Elizabeth Derryberry
Associate Editor, Journal of Animal Ecology

Former and current students and curators at the Louisiana State University Museum of Natural Science. Names: Left-right: Kevin Burns (Curator, San Diego State University Museum of Diversity), Liz Derryberry (faculty, Tulane University), Andy Kratter (Collection Manager, University of Florida Museum), Phil Stouffer (faculty, LSU), Matt Carling (Curator, University of Wyoming), Sinéad Borchert (Stouffer lab, LSU), Robb Brumfield (Director, LSU Museum of Natural Science), Clare Brown (Sheldon lab, LSUMNS), Ryan Burner (Brumfield lab), Angelica Hernandez Palma (Stouffer lab, LSU), Mark Robbins (Collections Manager, Kansas University), Terry Chesser (Curator, Smithsonian), Fred Sheldon (Curator, LSU MNS), Oscar Johnson (Brumfield lab), Jared Wolfe (USDA Forest Service).

Former and current students and curators at the Louisiana State University Museum of Natural Science. Names:
Left-right: Kevin Burns (Curator, San Diego State University Museum of Diversity), Liz Derryberry (faculty, Tulane University), Andy Kratter (Collection Manager, University of Florida Museum), Phil Stouffer (faculty, LSU), Matt Carling (Curator, University of Wyoming), Sinéad Borchert (Stouffer lab, LSU), Robb Brumfield (Director, LSU Museum of Natural Science), Clare Brown (Sheldon lab, LSUMNS), Ryan Burner (Brumfield lab), Angelica Hernandez Palma (Stouffer lab, LSU), Mark Robbins (Collections Manager, Kansas University), Terry Chesser (Curator, Smithsonian), Fred Sheldon (Curator, LSU MNS), Oscar Johnson (Brumfield lab), Jared Wolfe (USDA Forest Service).

East Africa’s Elephant Architects

I can see elephants in my backyard—at least fifteen of them, youngsters and grownups. They are a few hundred meters off, but distinctive amongst the thorn trees, and my eyes drift to them every time I look up from the computer screen.

Elephants as seen through the window as I sat down to write this post at Mpala Research Centre in Kenya, July 5th 2015

Elephants as seen through the window as I sat down to write this post at Mpala Research Centre in Kenya, July 5th 2015

In the 12 years that I’ve been working here at the Mpala Research Centre in central Kenya’s Laikipia Highlands, elephants have grown both more abundant and more tranquil, less prone to howl at passing cars. This shift has both deep and shallow historical roots: Laikipia’s colonial legacy of large landholdings, a decentralized local conservation movement, the diminishing profitability of livestock, the rise of ecotourism, urbanization, globalization. These factors, independently and synergistically, have helped Laikipians tolerate elephants, and tolerance is reciprocated. Sitting at this little desk in this tiny sliver of equatorial Africa, I find it easy not to stew about the future of elephants. I mean, look at them out there.

Elephants in Laikipia’s clay-soil, with Mt. Kenya and Acacia drepanolobium trees in the background

Elephants in Laikipia’s clay-soil, with Mt. Kenya and Acacia drepanolobium trees in the background

In Mozambique’s Gorongosa National Park, where I spent the previous month, things are different. Gorongosa’s elephants are rebounding after having nearly been exterminated during two decades of war (another colonial legacy). The story of exactly what happened to the elephants during those years remains to be told, but the anecdotes are depressingly credible: ivory swapped for guns used to shoot more elephants to buy more guns. Since 2004, a sweeping restoration effort has bought the time and space for elephant numbers to quintuple, but erasing the biological and cultural legacies of the slaughter will take centuries. Gorongosa’s elephants, many of them tuskless, are anxious on the best of days; on the worst of days, they try to kill you.

A herd of elephants, including tuskless females, in Mozambique’s Gorongosa National Park

A herd of elephants, including tuskless females, in Mozambique’s Gorongosa National Park

Just as you can read human history in elephant behavior, you can read elephant history in the landscape. Anyone who has ever seen an elephant feeding can appreciate their ability to maintain open savannas (or, more pejoratively, to destroy woodland) by felling large trees. Accordingly, the human-elephant détente in Laikipia has left footprints. When my colleague Truman Young started working at Mpala in the early 1990s, the tree Acacia hockii was locally common. Now, it is almost gone; a team of botanists recently found one individual growing in an inaccessible rock-slope refuge—a great find. Because each tree species is the hub of many ecological interactions, elephants’ feeding habits can create shockwaves throughout entire communities. The hook-thorned Acacia mellifera, whose cage-like architecture provides daytime sleep-sites for nocturnal bushbabies, seems to be declining on Mpala’s clay-rich soils as elephant densities increase. As goes mellifera, so should go bushbabies.

In Gorongosa, conversely, the prolonged absence of elephants and other large herbivores has triggered substantial expansion of woody vegetation. Work by my student Josh Daskin has shown that tree cover has more than doubled in Gorongosa’s Rift Valley habitats over the past 35 years. This too has undoubtedly had cascading impacts on Gorongosa’s other fauna.

This ability of elephants to transform landscapes has motivated a large body of research, including our study in Journal of Animal Ecology. We showed that fire—another potent form of disturbance in savannas—amplifies elephant ecosystem engineering in Mpala’s clay-soil habitats. The vast majority of trees in these soils are whistling-thorns (Acacia drepanolobium), which elephants rarely touch. Why? Because A. drepanolobium is well-defended via its co-evolved relationship with ants that protect the trees from herbivores (elephants dislike getting ants up their noses). The experiment involved torching a series 900-m2 patches, inside and outside of plots from which elephants and giraffes are excluded using two-meter-high electrified wires.

Electrified wires exclude elephants from experimental plots

Electrified wires exclude elephants from experimental plots

These controlled burns killed many of the ant colonies, depriving trees of their symbiotic guardians. In the elephant-free zones, the antless trees stayed upright. But outside the fenced areas, elephants zeroed in on the newly vulnerable trees and wreaked havoc.

Of course, ‘havoc’ depends on your point of view. For arboreal dwarf day geckos (Lygodactylus keniensis), which are the most numerous vertebrate animals in this habitat, the patches of toppled trees were prime real estate. Browsing elephants snap stems and large branches, creating small cracks and crevices that geckos use as refuges and nest sites. In our experiment, gecko abundance quickly doubled in plots affected by both elephants and fire—a synergistic effect, meaning that the combined impact of the two disturbances together was greater than the sum of each independently.

An elephant feeds on Acacia mellifera at Mpala Research Centre, Kenya

An elephant feeds on Acacia mellifera at Mpala Research Centre, Kenya

But the gecko housing bubble was short-lived. After 12 months, severely damaged trees in the unfenced plots began to collapse, reducing gecko densities from the astronomical levels (up to 1,100 per hectare!) attained in the first year of the experiment. In the fenced burned plots, meanwhile, scorched trees were slowly decaying, creating novel lizard-friendly fissures. After 16 months, gecko abundance was equally high in all burned plots, regardless of elephants. Thus, fire by itself had the effect of doubling gecko abundance; it’s just that the effect emerged more rapidly with an assist from the elephants. In contrast, elephant effects materialized only in burned plots and then melted away.

The importance of fire-elephant interactions in African savannas is widely appreciated, but our study was unusual in two respects. First, due to the difficult-to-tame nature of both elephants and fire, most prior studies have relied heavily on observational data. By manipulating both fire and elephants in a controlled and replicated experiment, we were able to quantify their interactive effects in the absence of confounding environmental variability. Second, although small animals constitute the bulk of biodiversity, prior studies of the elephant-fire nexus have focused almost exclusively on vegetation. Intuition suggests that these ‘destructive’ forces should negatively affect arboreal animals (and in some cases they surely do), yet our study showed that their effects can be positive—and even more positive in combination, at least temporarily—by rearranging tree architecture.

As illustrated by the divergent scenarios unfolding in Laikipia and Gorongosa, elephant populations are acutely sensitive to the human dramas in which they are embedded. Their profound ecological impacts, like those of fire, stir strong emotions and spark debates that divide management teams. What is the right number of elephants, and how often should a savanna burn? Science cannot adjudicate those subjective questions, but it can help us anticipate the likely consequences of their answers. Observational, experimental, and modeling studies each independently illuminate important facets of this problem; together, their effects are synergistic.

Rob Pringle
Princeton University
Twitter: @rob_pringle

For more of Rob’s photos please see the slideshow

All photographs by Robert M. Pringle

American Ornithologists Union focuses on fledging early career professionals

It is a hot Friday morning, the second to last day of an intimate AOU-COS meeting on the University of Oklahoma campus, and a big day for my lab. A number of my students are giving their first conference talks and have the jitters. I’ve listened to renditions between sessions and late into the night. I remember the not too distant past when I stood nervous in my PI’s room, making yet another attempt to get through my talk in 12 minutes flat. My students’ talks seem so much better than the first ones that I wrote. I’m proud of them, although this doesn’t allay their nervousness one bit. This is also a big day for me, as I’m giving my first plenary. The invitation was unexpected. I am a third year faculty member, still making all the typical fledgling mistakes – ‘wait that $5000 centrifuge rotor doesn’t actually work with our plates?!’ – and only distantly considering a keynote should my H-index ever see the backside of 50 (side note – mine is 14).

This opportunity, and many similar ones occurring right now in AOU, is part of the efforts of Scott Lanyon, the current president, to embrace and encourage early career professionals. This is the second AOU-COS meeting to devote an afternoon to lightning-5-minute-auto slide advance talks by young professionals followed by a mentoring social. Each early career person is paired with a senior scientist and given detailed feedback on presentation style and interview techniques. This occurred yesterday and the room was packed, everyone eager to learn about the budding research programs of ten ornithologists. I wished this opportunity existed when I was about to enter the job market. Knowing how to sell your ideas in a cogent, exciting package is key in this tight job market. Several of the presentations were spotless, and the research presented cutting-edge. I suddenly realized that perhaps I wasn’t so early career anymore; with this young group about to fledge, it was time to stop reminiscing and get on with my own presentation. Wish me luck!

Elizabeth Derryberry
Associate Editor, Journal of Animal Ecology